


The Effects of One Mistake

by heartsdesire456



Category: Teen Wolf (TV)
Genre: Angst, Canonical Character Death, Gen, Humor, M/M, Past Relationship(s), past adultery
Language: English
Status: Completed
Published: 2014-01-13
Updated: 2014-01-13
Packaged: 2018-01-08 13:30:21
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 2,638
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/1133218
Author URL: https://archiveofourown.org/users/heartsdesire456/pseuds/heartsdesire456
Summary: <blockquote class="userstuff">
              <p>Peter shook his head with a sardonic smile. “I’m sorry you’ve blamed yourself all this time, but the truth is, I was the ‘why’, Derek. You were the ‘how’.”</p><p>“Wait, <i>what</i>? Why the hell were you the ‘why’?” </p><p>“Because you’re not the only werewolf who was having an inappropriate relationship with a hunter."</p>
            </blockquote>





	The Effects of One Mistake

**Author's Note:**

> Random ficlet that came to me at fucking 6:50am when I was trying to go to bed. *headdesk*
> 
> Just a little ficlet, hopefully you'll like it!

Watching Derek fall apart at Deaton’s office after he’d been doused in magical fairy dust or what the fuck ever it was had been pretty terrible, if you asked Stiles. He still didn’t like the guy that much, but seeing a grown man curled up in a ball crying and apologizing over and over for his family dying to nobody in particular was _hard_. Even Peter, who had never shown any real affection for his nephew, looked positively green with a side of murderous as Derek curled up in the corner and cried. Deaton had informed them that, unfortunately, there was nothing to do but let it get through his system. Chris Argent had agreed to stay behind with Scott and Stiles so that Lydia could get Isaac home to heal. Allison stayed with her father just in case. 

After the magic seemed to wear off, Scott went to go check on Isaac and Stiles and Allison agreed to go with Peter and Chris to take Derek home. When they got him home, Cora was waiting and John was still there, having stuck around when he took her home. Derek was finally lucid once he got out of the shower, but he clearly remembered his reaction because he looked both terrified and ashamed as he sat down and accepted the water John offered him. Nobody spoke for a while before Allison fidgeted beside Stiles and opened her mouth.

“Derek… whatever you think happened… it wasn’t your fault what Kate did to your family. She was crazy and- and she just probably wanted to impress Gerard,” she said gently. “I don’t know why you think it’s your fault, but it’s not.”

Derek snorted weakly, rubbing the heels of his hands into his eyes. “How do you think Kate knew how to get into the house and when everybody was there?” he gritted out.

Allison frowned. “Um… I didn’t think of that part?” she tried.

John eyed Stiles and Stiles cringed. “Dad, don’t ask me-“

“Stiles found out about it because he’s smarter than I ever was,” Derek interrupted, then looked down at his hands. “I was sleeping with Kate Argent and she asked me questions and I told her,” he admitted out loud for what Stiles was pretty sure was the first time ever.

Cora gasped, Allison paled, Chris’s head snapped up in shock, and John hesitantly leaned on the couch beside Derek. “Son… weren’t you sixteen when-“

“She was a substitute teacher,” Derek whispered and John’s frown deepened.

“A substitute teacher. A _teacher_ \- even a substitute – is a person in a position of authority. No matter how consenting it is, even if you had been eighteen, that’s statutory rape, Derek. You didn’t ever tell anybody-“

“I wasn’t going to admit that I was the reason my _whole family_ was _dead_!” Derek snapped, looking up at him with a dark and pained glare.

John ran and hand over his face. “Derek, you were just a child.”

“I still got them killed-“

“No, you didn’t,” Peter said finally, uncrossing his legs as he leaned back in his chair, running his hands through his hair. “Derek, she used you to learn the _how_ , but you weren’t the _why_ ,” he said, then looked at Derek. “And if I had known what she was doing to you, I would’ve ripped her throat out before she ever got a chance to touch you again, that fucking pedophile bitch,” he added bitterly.

Derek shrugged. “She was insane, like Allison said, that’s all the ‘why’ she needed,” Derek said.

Peter shook his head with a sardonic smile. “I’m sorry you’ve blamed yourself all this time, but the truth is, I was the ‘why’, Derek. You were the ‘how’.”

Stiles frowned. “Wait, _what_? Why the hell were you the ‘why’?” 

Peter glanced up at Chris who sighed when he met his eyes and let his head hang as he stood leaning against the wall behind John. “Because you’re not the only werewolf who was having an inappropriate relationship with a hunter, Derek,” Peter admitted.

Cora and Stiles both gasped out loud as they looked between Chris and Peter and John gave Peter a suspicious glance. Allison just stared at her father in shock. “Wait a minute, _what_?” John asked sharply.

“You were cheating on mom?!” Allison asked in shock and Chris cringed, but nodded.

“Kate found out. Even if I hadn’t been married to your mother, it was still highly inappropriate because he was a werewolf and he was a… well I wouldn’t even say man, I’d go with boy,” he said with a dry chuckle. “No idea how old you were,” he said to Peter, who smiled ruefully.

“I was twenty-two,” he said and Stiles frowned.

“Whoa, wait up, you mean you’re only _twenty-nine_?!” he asked skeptically.

Peter nodded. “Yes, being in a coma ages you greatly, I’m afraid. Being dead didn’t help,” he added with a shrug. “I didn’t look any older at twenty-two than you do now, really.”

John shot Chris a look and he shrugged. “He was legal,” he offered and John shook his head.

“You cheated on your wife with a _kid_ , Argent?” he asked and Allison looked up.

“We didn’t live anywhere near here, though,” she said slowly. “How…?”

Chris rubbed at his face. “We lived in Oregon, remember? Sometimes when I was away on ‘business trips’ they were hunts and we didn’t hunt the wolves here, but we did hunt in this area. The Hale pack weren’t the only ones around. Others came through all the time.”

Derek was glaring at Peter. “You slept with a _hunter_ knowing what he was?” he demanded. “I didn’t know any better, I was sixteen and confused and controlled by hormones, but you knew better.”

Peter smirked. “What better way to get back at my bossy sister controlling my life to the point of erasing memories sometimes and keeping me _grounded_ like I was a child and she was my mother than to go to a bar, get picked up by a hunter, and spend a weekend holed up in a hotel room fucking like the animal he didn’t know I was?” he asked and Derek gave him a disgusted look. “My luck, the one I met knew I was a werewolf, knew _who_ I was, and resisted. It made me try harder,” he said and Cora just shook her head.

“You really were always psychotic, weren’t you?” she asked and Peter shrugged.

“You say psychotic, I say a bratty youngest sibling with a taste for sexual deviancy,” he said and Stiles cringed.

“Well that’s gonna haunt my nightmares,” he muttered and John nodded, making a similar face of disgust.

Allison shook her head. “What I don’t understand is why you cheated on mom. I would’ve been eleven by then! Did you cheat on her before? Or after? Was it just the one time or was it a pattern?” she asked.

Chris leaned back, closing his eyes as his head thumped against the wall. “Because I never wanted to marry Victoria in the first place,” he admitted, earning surprised glances from most of the room besides Peter. “Allison, your mother was my wife and I did love her by the end. But mostly because I’d been living with her for eighteen years and you can’t spend that long with someone and not care about them a lot. However, the truth is, I married your mother because my father wanted me to.”

“ _What_?!” Allison asked and he nodded apologetically.

“Her family were hunters and she was my age and she was a ‘perfect choice’ for an Argent female to be leader after my mother died since Kate was so young. As soon as I finished college, they pushed for me to marry her so I did and immediately my father wanted grandchildren so we started trying for a baby and had you. And I loved you more than anything in the world even before you were born,” he said in a tight voice. “And for a while I loved Victoria because she’d given me the most beautiful baby girl in the world… but it all came back to the fact she wasn’t who I’d have chosen on my own.” He smiled sadly. “I loved her as my best friend. Not as my wife. I knew better than to upset the system, though. I’d have stayed married to her until I was old if she hadn’t-“ He swallowed hard and looked down. “Don’t think I didn’t love her, Allison.”

Allison took a few calming breaths and looked up at her father. “Did she know? About… him?” she asked, and Chris cringed.

“No. She didn’t. He was the only one and I thought about telling her so many times, especially when it kept happening but… well my sister found out and ‘fixed the problem’,” he admitted sadly.

Stiles eyed them suspiciously. “So it ‘kept happening’? How long are we talking? Like… a few times or ‘full on affair’?”

Chris cleared his throat awkwardly. “A few months. Every other weekend,” he admitted. “I tried to stop but it was… exciting,” he said with an uncomfortable cringe.

Peter nodded his head with an almost ashamed look. “It wasn’t love or anything like that, it was just… heat. Attraction. Passion. I was twenty-two and I’d never been with an older man and it was better sex than I’d ever had, and he’d been married to a woman he saw more as a friend than a lover for twelve years, so a young, strong, insatiable werewolf was definitely a candidate for spicing things up.” He shrugged. “Not to mention the guilt-fueled hate sex,” he added.

Chris chuckled darkly. “Pretty sure I broke your arm the first time and still had you over a table later-“

“OKAY! UNDERAGE EARS PRESENT!” Stiles cried suddenly, looking scarred for life.

Cora shuddered. “Related ears.”

“I think you broke Allison,” John added, looking worriedly at Allison, who was frozen, staring a head with a look like she was about to vomit. 

“I know the feeling,” Derek grumbled to Allison, looking more than a little ill himself. 

Peter gave Chris a searching look. “I always did wonder how Kate found out, Christopher,” he said and Chris gave him a sad smile.

“Followed me. Victoria had mentioned I was gone on a hunt but she knew there weren’t any planned for that weekend.” Chris rubbed at his eyes. “I didn’t know she knew. I didn’t know it even after the Hale house burned down. I genuinely thought it was just a tragedy. I had no idea my sister or any other hunter had started that fire. But when people started making noise about it being arson, I thought back. It had been years but I remembered running into Kate on the border on my way back at a gas station. She said she was headed south on a hunt and I had no reason to think she wasn’t. She didn’t ask where I’d been so I assumed nothing was suspicious.” He looked up. “Two days later I read about the fire. I didn’t connect the dots and I am sorry for that. If I’d known she killed innocent people, I’d have turned her in.”

Peter shrugged. “I prefer my method of fixing the problem better,” he admitted and Stiles glared at him when Allison flinched. “What? She tried to kill Derek because her mother committed suicide after he bit her. I killed Kate because she directly murdered my family and left me burned and broken for _six years_. What’s that saying about stones and glass houses?” he asked Allison.

Derek shrugged. “You tried to get me killed by telling me I could save Cora,” he pointed out and Peter shrugged with a flippant little smirk.

“I like Cora. She’s more fun than you are,” he said dismissively. “It worked, didn’t it? Telling me you wouldn’t have done it even if you knew you would die?” he asked and Derek hesitated then shook his head. “Exactly. 

Cora rolled her eyes. “I still can’t believe you were sleeping with not just a _hunter_ , but Chris Argent. Especially after what you told me and Stiles about Gerard Argent.”

Peter sighed dramatically, rolling his eyes. “You’re seventeen, you tell me what anybody with loose morals and eyeballs that’s attracted to men would find appealing about hot, filthy, passionate sex with someone who looks like that at this age, nonetheless what he looked like seven years ago,” he said, gesturing to Chris, earning an annoyed snort.

Cora cringed. “He’s old enough to be my father, Peter. Ew.”

Stiles shrugged. “I dunno, dude, to be as old as he is, Argent is sort of hot. I mean it’s gross cause he’s _a teenger’s dad_ but I mean, have you seen the way he walks around with half his buttons undone?” he asked and everybody shot him looks ranging from horrified (Allison), offended (Chris), confused (Cora), and even amused (Peter). Stiles rolled his eyes. “Oh come on, I have eyes!”

“And since when are they looked at old men?” John asked Stiles, and Stiles flushed. “Oh God, tell me I don’t have to go kill someone,” he groaned and Stiles spluttered.

“DAD! No!” he hissed, then slapped a hand over his face. “For the record, I tried to tell you I like boys, you just didn’t believe me!” he pointed out. “And I said ‘I can see the appeal’, not ‘I’m attracted to dudes my dad’s age. Ew. Seriously? Gross.”

“Oh God,” John groaned, rolling his eyes. “Why me?”

Peter chuckled. “I’m beginning to see where Stiles gets it,” he said, and John just held up a hand to stop him.

“Please no more. I just can’t. Not right now-“

“Hmmm, you’re single right?” Peter asked with a teasing smirk and John glared.

“I will shoot you, Hale,” he said, then cringed when he saw the way Peter’s eyes were moving over his body. “Alright, I’m out. I think I need a shower now,” he said, grabbing a handful of Stiles’s shirt to pick him up off the couch. “C’mon, not leaving you here for when they all finally kill him.”

Stiles nodded. “Don’t blame you, Dad. I totally thought I was gonna get raped that time he kidnapped me. It was horrifying. I don’t even think he means to be as creepy as he is, it’s just natural.”

“We’re out too,” Allison said, standing up. “We have a lot to deal with, but I’m too tired for it tonight,” she said to her dad, and he nodded, sliding his arm around her shoulders as he let her lead them to the door.

Cora watched them leave then glanced at Derek, who raised an eyebrow. “Oh hell no, I’m not leaving you alone with him, he might try to trade you for a blowjob,” she said and Peter rolled his eyes and stood up to head upstairs.

“Please, as pretty as Derek is, I could get an orgy,” he said, smirking at the way Cora glared and curled an arm protectively around her brother. Derek just rolled his eyes and let his head drop, clearly contemplating killing both of them just to end his own misery. 

Peter stopped at the top and looked down at them and closed his eyes, tapping his finger on the railing as he watched the only two members of his family he had left. Derek may have blamed himself all this time, but the truth was, Peter was far from unaware that it was his fault those children were orphans. He glanced out the window and saw Chris getting into the car with his daughter, the entirety of their world as well, and shook his head. 

It was crazy what one stupid decision could do to two people’s entire families.


End file.
